Well, it turned off this voter:

“I was a Huckabee supporter until about a week ago,” said Brian Wright, a Fort Madison resident. “And then I heard his comment about Pakistan today.”
[…]
“Knowing that Senator Fred Thompson has foreign policy experience with the world leaders, I believe he’s the best choice,” said Wright, adding that Huckabee turning Bhutto’s assassination into an immigration issue “turned me away from him.”

What’s funny about this is that Huckabee brought up immigration to appeal to men:

The campaign official admitted that Huckabee’s tough immigration talk is also aimed at helping him win male GOP voters in Iowa — a bloc the official concedes the campaign has been losing ground with.

Um…it looks like it backfired.
BTW, so much for the analyst who said this wouldn’t effect the race:

“Mike Huckabee is a populist. His comments on Pakistan reflect a populist understanding of the crisis, which, is to say, not much,” Schneider said. “Sure, the political establishment is snickering, but I doubt that his misstatements bother his supporters much.”

Related Post:
Senior aide to Huckabee: He has “no foreign policy credentials”